Recent content by omgitsmonica

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    Calculating a Planetary Year for Krau?

    Does T increase by 1.6, too?
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    Calculating a Planetary Year for Krau?

    Homework Statement "Yoda has just discovered planetary system consisting of star Dagobahr and its two planets: Rool and Krau. Planet Rool has average orbital radius 1.6 times as big as planet Krau. If planet Rool orbits Dagobahr in 2.9 Earth years, how long is a year for the resident of...
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    Pressure and Temperature and Heat

    No, then it doesn't. So if nRT is constant, the two PVs should be the same. Thank you so so much for all your help.
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    Pressure and Temperature and Heat

    Okay, so, for the second one, I looked through my textbook and found the equation PV=(2/3)K. I tried using that equation (because it doesn't consider temperature or N) but I came up with a ridiculously low number. Is that right, or am I completely off base?
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    Pressure and Temperature and Heat

    THANK YOU THANK YOU THANK YOU. Just one question, and then I'll do the work on my own, I promise -- for the ideal gas equation, where N determines the number of molecules, how do I figure out how many molecules there are?
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    Pressure and Temperature and Heat

    Homework Statement An ideal gas occupies a volume of 0.3 m3 at the pressure of 400 kPa. If the volume changes to 0.85 m3 and the temperature remains constant, what is the pressure of the gas? Give answer in kPa. OR If 500 cal of heat are added to a gas, and the gas expands doing 394 J...
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    Calculate Density of Solid Object Floating in Water

    If the density of water is one, and its floating, than it must be less than one? How do I figure out exactly what it is, though? I don't have the mass or the exact density or the volume, so my formula is useless...
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    How Does Pipe Expansion Affect Water Pressure?

    Homework Statement Water flows at 6.1 m/s in a horizontal pipe with a pressure of 3 ´ 104 N/m2. If the pipe widens to twice its original radius, what is the pressure in the wider section? Give answer in Pascals. Homework Equations volume = length x area rate = volume / time rate =...
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    Calculate Density of Solid Object Floating in Water

    Homework Statement A solid object floats with 54% of its volume beneath the surface of the water. What is the object’s density? Give answer in g/cm3. Homework Equations Density = mass/ volume The Attempt at a Solution I know that the density must be more than one, because the...
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    Circular Motion/Centripetal Forces

    I imagine it would be the acceleration, because the direction of motion would be changed. Or does that not matter, like trajectories?
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    Circular Motion/Centripetal Forces

    F=ma, so 80N=2.1a so 38.1=a Ac=v2/r, so 38.1=v^2/.5 So v^2=19.05, so v = 4.36 Is that right?
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    Circular Motion/Centripetal Forces

    Homework Statement A 2.1 kg mass is attached to the end of a .5m string. The system is whirled in a horizontal circular path. If the maximum tension that the string can withstand is 80N, what is the maximum speed in m/s of the mass if the string is not to break? Homework Equations...
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    Angular Acceleration: Find Angle in 2 Seconds

    Homework Statement A wheel accelerates with constant angular acceleration of 6 rad/22. If the initial angular velocity is 6 rad/s. what is the angle in degrees that the wheel rotates through in 2 seconds? Homework Equations 360 degrees = 2pi radians The Attempt at a Solution...
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    Comparing Impulse in Collisions: Which Ball Experiences a Greater Magnitude?

    impulse equals change in momentum. so are they the same, since momentum is conserved?
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    Calculate Power of 50 kg Boy Running Up 10 m in 7 s

    I don't know how to do energy gains...